Channel Five senior management have been told it is "business as usual" after its first day under Richard Desmond's ownership.

But sources within the industry have questioned the channel's ability to hit a target of doubling its TV ad share.

The Five chief executive, Dawn Airey, is understood to have reassured senior staff at a meeting attended by senior executives from Desmond's company Northern & Shell, including the editorial director, Paul Ashford.

Staff were told that the N&S team would spend several weeks "getting to know the business" before making any major decisions on the future strategic direction of the channel. However, given Desmond's history of cost-cutting, media analysts have already raised the prospect of job cuts among the almost 300 Five staff.

Desmond has pledged to top up the broadcaster's total budget to about £1.5bn over the next five years, including new investment of £50m to £100m a year to boost programming and the equivalent of £20m promoting the channel and its shows in a marketing campaign in publications including OK!, the Daily Star and the Express titles, while maintaining that the channel will not be taken downmarket with an increase in public service content such as news and current affairs.

He is also expected to return Five to video-on-demand joint venture Project Canvas, which the channel pulled out of earlier this month due to financial constraints, and has also pledged to continue with deals for shows including CSI and Neighbours. Five posted a loss of €41m (£34m) last year, while operating losses were €10m, with €22m in programme writedowns.

Desmond is eyeing up big-name programmes to drive audience, and therefore hopefully TV ad deals with agencies on behalf of advertisers, with Endemol's Big Brother touted as a good fit when its deal with Channel 4 concludes later this year. Desmond originally jointly bid for Channel Five with Endemol, as reported by MediaGuardian.co.uk.

However one of Desmond's plans, to raise Five's share of the TV advertising market from 7% to 14%, has been deemed impossible by a number of sources in the media industry.

Five has suffered in recent TV trading seasons, the period at the end of the year when media agencies negotiate most of their annual ad spend with the TV ad sales houses on behalf of clients, as the smallest mainstream player in a market increasingly characterised by size through consolidation.

It was thought that Desmond might look to do a sales deal with Channel 4, ITV or Sky – perhaps the most obvious choice as third in the market representing the least chance of regulatory scrutiny – in order to stop the almost inevitable battering of Five's position in this year's trading season. Desmond is not thought to have opened up any formal discussions about a potential ad sales contract and, at least publicly, seems to be set to pursue a strategy to attempt to build Five's scale independently.

One senior media agency executive said: "They do offer good value as long as you put the right share [of ad spend] in and they could push to 9.5% or even 10% in the next few years."

The media agency source argued that Five needed a two-pronged approach to gain market share. The first is to bury the hatchet with several agencies that have pulled ad spend off the channel – Carat and ZenithOptimedia have been reported in the past as having issues with Five – and win over "under-supporting agencies".

The second is to focus on taking on Channel 4 and BSkyB, which the media executive argued face trading issues over audience deals and prices – not ITV's sales operation, as Desmond did in the weekend press.

For example Channel 4, which has had a barnstorming recovery this year, will have a Big Brother-sized audience hole that it has not replaced that advertisers may look to fill elsewhere.

"There is share [of TV advertising] that Five could definitely pick up if they can resolve their issues in the market and and take money from others [C4 and Sky] if advertisers do not want to exacerbate their existing problems," said the media agency source. "Channel Five needs some big news. I can seem them getting £30m a year for five years from 'unsupported agencies' and maybe the same again from a signing like Big Brother – but not much past that."

The source argued that a cross-sell by Desmond's newspaper sales operation would not work and that the best option was to keep Five's TV sales operation largely intact.

"TV is much more complex than I think they [Desmond] might realise and he should keep the sales people, the savvy ones," he said.

Another source argued that if Desmond does "go it alone"with TV sales this season, which runs until about Christmas, there is a good chance that he will consider linking up with a bigger player next spring if Five suffers in negotiations.

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